从全国各地采集土样６００多份，经富集、初筛、二次筛选与复筛获得一纤维素酶活比较高的野生纤维素酶产生菌Ｃ１０．经鉴定为黑曲霉（Ａｓｐｅｒｇｉｌｌｕｓｎｉｇｅｒ）．以Ｃ１０为出发菌株，经紫外线、亚硝基胍、６０Ｃｏ－γ射线和硫酸二乙酯等物理化学诱变处理，最后得到一株突变株Ｃ６６．Ｃ６６菌株酶活与国内外高酶活的菌株比较，其纤维素酶各组份酶活均高于对比菌株，可以认为Ｃ６６是一株目前国内外纤维素酶活较高的菌株． More than 600 soil samples were collected from all over the country. After enrichment, preliminary screening, secondary screening and re-screening, a C10 strain with high cellulase activity was obtained. It was identified as Aspergillus niger. C10 as the starting strain, the UV, nitrosoguanidine, 60Co-gamma rays and diethyl sulfate and other physical and chemical treatment, and finally get a mutant strain C66. C66 strain activity compared with domestic and foreign high-enzyme activity of the strain, the cellulase activity of each component were higher than the control strains, C66 can be considered as a strain of cellulase activity at home and abroad.